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<TITLE>Magic-8.3 Command Reference</TITLE>
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<H1> <IMG SRC=graphics/magic_title8_3.png ALT="Magic VLSI Layout Tool Version 8.3">
     <IMG SRC=graphics/magic_OGL_sm.gif ALIGN="top" ALT="*"> </H1>

<H2>corner</H2>
<HR>
Make L-shaped wires inside the cursor box.
<HR>

<H3>Usage:</H3>
   <BLOCKQUOTE>
      <B>corner</B> <I>d1 d2</I> [<I>layers</I>] <BR><BR>
      <BLOCKQUOTE>
         where <I>d1</I> and <I>d2</I> are valid manhattan
	 <A HREF=direction.html><I>directions</I></A>, and
	 <I>layers</I> is an optional comma-separated list
	 of valid paint layers.
      </BLOCKQUOTE>
   </BLOCKQUOTE>

<H3>Summary:</H3>
   <BLOCKQUOTE>
      The <B>corner</B> command makes L-shaped wires inside
      the cursor box, filling first in direction <I>d1</I>,
      then in direction <I>d2</I>.  If no <I>layers</I> are
      specified, then the cornering algorithm is applied to
      all layers crossing the cursor box boundary opposite
      to direction <I>d1</I>.  If <I>layers</I> is specified,
      the cornering algorithm is applied only to those layers
      specified.  The usage of <B>corner</B> is similar to
      that for the command <B>fill</B> (q.v.).
   </BLOCKQUOTE>

   <BLOCKQUOTE>
      Below is an example showing how the cornering algorithm
      responds to the command <B>corner n e</B>.  First it
      finds layers crossing the cursor box boundary to the
      south (opposite to the first specified direction,
      <B>north</B>), and then extends these layers as wires
      first to the north, then to the east.  The position of
      the layers leaving the box to the east is such that
      the same distance is maintained from each layer to the
      north side of the box at the exit point as it was
      from each layer to the east side of the box at the
      entrance point.

      <CENTER>
      <IMG SRC=graphics/corner1.gif>
      <IMG SRC=graphics/corner2.gif> <BR>
      <I>Figure 1: The cornering operation in response to the layout
      shown, given magic command <B>corner n e</B></I>.
      </CENTER>
   </BLOCKQUOTE>
   

<H3>Implementation Notes:</H3>
   <BLOCKQUOTE>
      <B>corner</B> is implemented as a built-in <B>magic</B> command.
   </BLOCKQUOTE>

<H3>Bugs:</H3>
   <BLOCKQUOTE>
      If the area in the box is not large enough for
      the cornering algorithm to produce the cornered
      wires, unpredictable results often result.
   </BLOCKQUOTE>

<H3>See Also:</H3>
   <BLOCKQUOTE>
      <A HREF=diretion.html><I>direction</I></A> <BR>
      <A HREF=fill.html><B>fill</B></A> <BR>
   </BLOCKQUOTE>

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<P><I>Last updated:</I> March 7, 2020 at 1:06pm <P>
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